The study aims to determine the role of human pulmonary surfactant in lung mechanics and whether or not alterations in the system occur and relate to acute pulmonary insufficiency states. A new micromethod will allow surfactant analysis in transplant donors and ultimately in acute lung injury states resulting in the adult respiratory distress syndrome (ARDS). Analysis of surfactant abnormalities will also be performed in postmortem lungs resulting from both the infantile respiratory distress syndrome and ARDS. Thus far 26 human lungs have been studied. Preliminary data strongly suggests a qualitative difference between male and female patients. A single male infant had a surfactant composition similar to the female pattern. A single case with ARDS has surfactant abnormalities. BIBLIOGRAPHIC REFERENCE: Fine, R., Silvers, G.W., Paul, G.W., Petty, T.L. and Filley, G.F. Effect of ventilation on single breath nitrogen washouts in excised human lungs. Clin. Res. 24, 122a, 1976.